How is it that depending on the setting, the same cat can be perceived as a homeless annoyance, a potential research subject or a thinking and feeling family member? The answer is bound up in our perception of non-human animals' capacity to experience emotions, and this book draws on contemporary evidence-based research, observations, interviews and anecdotal case scenarios to explore the growing knowledge base around animal emotion. Acknowledging that animals can experience feelings directly affects the way that they are perceived and treated in many settings, and the author explores the implications when humans apply - or ignore - this knowledge selectively between species and within species. This information is presented within the unique context of a proposed hierarchy of perceived non-human animals' emotional abilities (often based on human interpretation of the animal's emotional capacity), with examples of how this manifests at an emotional, spiritual and moral level. Implications for specific groups living with, caring for or working with non-human animals are examined, making the book of particular interest to those working, studying or researching in the veterinary professions; animal ethics, law and welfare; and zoology, biology and animal science. This book will also be fascinating reading for anyone interested in simply learning more about the animals with whom we share this planet. For some readers, it will validate the reciprocal emotional bond they feel for living creatures. For others, it will raise questions about the moral treatment of sentient non-human beings, breaking down the human protective barrier of cognitive dissonance and activating a cycle of change.